Establishing a point-to-point connection between users who are connected via communications terminals to a communications network generally requires that the network address of each connecting user be known to all other connecting users. Many network communications service providers, such as Internet Service Providers (ISP's), assign users a different network address, such as an IP address, each time they connect to the network, making foreknowledge of a particular user's network address impossible.
Some commercial and non-commercial services maintain network servers connected to a network. Users who connect to the network provide their current network address and other identifying information to one or more of these network servers. This information is made available to other users connected to the network for purposes including point-to-point communications. Such services include Internet Relay Chat (IRC), for which software is commercially available from Surfing Squirrel Productions, Inc., Microsoft User Location Service (ULS), commercially available from Microsoft Corporation, and the Automatic Call Distribution System (ACD), commercially available from Executone Information Systems, Inc.
A user wishing to locate another user may connect to a network server that records user information in order to determine the other user's network address. A user usually locates another user by looking for the other user's electronic mail address, one or more nicknames that the other user often uses, or other identifying information. The effective use of such identifying information is limited inasmuch as a single user might have multiple electronic mail addresses, multiple users might use the same nickname, or a user might be connected via another user's network connection.
Unfortunately, services like those mentioned above do not generally provide for the unique identification of each user, thereby facilitating accurate location a specific user. Furthermore, such services require that users actively seek out other users, often from among several hundreds or thousands of users known to a server to be connected to a network at any given time. Such services also do not enable a user to limit who may access that user's identification information.